Three-dimensional (3D) television has been a technology trend in recent years that intends to bring viewers sensational viewing experience. Various technologies have been developed to enable 3D viewing and the multi-view video is a key technology for 3DTV application among others. To exploit the inter-view redundancy, 3D coding tools such as inter-view motion prediction (IVMP) have been integrated to conventional 3D-HEVC (High Efficiency Video Coding) or 3D-AVC (Advanced Video Coding) codec.
FIG. 1 illustrates the basic concept of the IVMP in current 3DV-HTM. For deriving the motion parameters of temporal inter-view Merge candidate (TIVMC) for a current Prediction Unit (PU, 110) in a dependent view, a disparity vector (DV) can be derived to locate a reference block (120) in a reference view. The derived DV can be based on the neighboring block disparity vector (NBDV) or the depth-oriented NBDV (DoNBDV) for the current prediction unit (PU). By adding the derived DV (130) to the middle position of the current PU (110), a reference sample location (120) is obtained. The prediction block in the already coded picture in the reference view covering the sample location is used as a reference block. If this reference block is coded using motion compensated prediction (MCP), the associated motion parameters can be used as the TIVMC for the current PU in the current view. The derived DV can also be directly used as the disparity inter-view Merge candidate (DIVMC) for disparity compensated prediction (DCP) of the current PU.
The corresponding area in a reference view may have plentiful motion information. However, according to the existing coding practice, only the motion information in the middle position of the area in the reference view is used for current PU in a dependent view. Therefore, it is desirable to develop an improved coding method that can further utilize the motion information of the reference block in the reference view.